Where or how can i turn in my canon for an upgrade or trade it in for a nikon?

I have a canon t1i(500d)
websites or stores would be great

Upgrading is nothing more than buying a new one after selling the old one. I haven't heard of a camera trade-in promo.

Sell your old camera on craigslist (you don't have to worry about bad checks or shipping charges) and then buy what you want